The March 11, 2011 Tōhoku M9.0 earthquake-induced tsunami and coastal inundation along the Japanese coast: A model assessment

Abstract

A high-resolution nested global-Japan coastal FVCOM system was used to simulate the March 11, Tōhoku M9 earthquake-induced tsunami waves and coastal inundation along the northeastern coast of Honshu Island in the western Pacific Ocean. Experiments were made with initial fields provided by five seismic rupture models under realistic conditions with inclusion of the Kuroshio, tides and wind forcing. Results show that the model-computed intensities and distributions of tsunami waves and subsequent coastal inundation could be significantly influenced by initial conditions, even though all five cases were capable of reproducing key features of the tsunami waves. Modeled tsunami waves featured a low dispersive, weakly nonlinear long wave controlled by hydrostatic dynamics. Non-hydrostatic effects only became significant when tsunami waves reached the inner shelf and the amplitude of the leading tsunami wave grew within O(1) of the local water depth (10 m or shallower). In both hydrostatic and nonhydrostatic cases, significant mixing occurred when the ratio of wave amplitude to local water depth grew to about 0.25 or greater. Model-predicted run-up was in good agreement with 2-D Nwave analytical solutions on the northern coast around South Iwate where inundation was small, but not in the central Sendai coastal region where inundation was large and 3-D wave dynamics became significant. The experiments suggest that once local bathymetry is accurately configured and the intensity and shape of the initial bottom movement can be predicted, this nested FVCOM system is capable of making accurate predictions of tsunami waves and coastal inundation.

Reconstruction of a meteotsunami in Lake Erie on 27 May 2012: Roles of atmospheric conditions on hydrodynamic response in enclosed basins

“…In particular, for wave conditions near coastal boundaries, FVCOM includes a ghost cell boundary approach that deters unrealistic damping of incoming waves and loss of energy in wave reflection. In addition, FVCOM has been successfully applied to a variety of coastal ocean, estuary, and lake environments, including validation of wind‐induced surface gravity waves [ Chen et al ., ], tsunami wave generation [ Chen et al ., ], and several barotropic cases [ Huang et al ., ]. In the Great Lakes, FVCOM has been successful in accurately predicting the amplitudes of coastal water level oscillations [ Anderson et al ., ; Anderson and Schwab , ; Niu et al ., ] and other hydrodynamic conditions [ Bai et al ., ; Fujisaki et al ., ; Nguyen et al ., ].…”

Initial spread of <sup>137</sup>Cs from the Fukushima Dai-ichi Nuclear Power Plant over the Japan continental shelf: a study using a high-resolution, global-coastal nested ocean model

“…Nesting with the global-FVCOM hindcast field with data assimilation of satellite-derived sea surface temperature and sea surface height, the high-resolution regional-coastal FVCOM model not only resolved a realistic regional circulation but also provided a better representation of the water exchange between FNPP and the surrounding ocean. Built on our success in simulating the observed tsunami and coastal inundation (Chen et al, 2013), we applied this model system to track 137 Cs over the period of 26 March-31 August 2011. Our studies aimed at assessing the impact of multi-scale physical processes on the initial spread of 137 Cs in the coastal region of Japan, which form the foundation for more realistic simulations with the inclusion of biogeochemical processes.…”

“…4). The vertical grid discretization was implemented using a hybrid terrainfollowing coordinate with a total of 45 layers (Chen et al, 2013). The s coordinate was used in regions with depth greater than 225 m, in which 10 and 5 uniform layers with a thickness of 5 m were specified near the surface and bottom, respectively.…”

The Generation of Nonlinear Internal Waves in the South China Sea: A Three‐Dimensional, Nonhydrostatic Numerical Study

“…The NLIW model was established based on the nonhydrostatic version of the FVCOM (Unstructured‐grid, Finite‐Volume Community Ocean Model; Lai et al, ). The FVCOM was originally a state‐of‐the‐art coastal ocean circulation model system but has been extended to regional‐, basin‐, and global‐scale studies (Chen et al, , ). The nonhydrostatic version of the FVCOM has been successfully employed to simulate the generation, propagation, steepening, and dissipation of large‐amplitude NLIWs in Massachusetts Bay, which demonstrates that the model is accurate and suitable for use in the current study (Lai et al, ).…”

“…The numerical study was configured by incorporating the external forcing into the model through an approach that has been successfully employed in previous studies (Chen et al, , ). To obtain a spatially varying initial stratification and background circulation for a realistic simulation, a 3‐D hydrostatic model was first integrated from August 2014 to the start time of the NLIW model.…”